/*
 * Copyright 2002-2023 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.core;

import org.springframework.lang.Nullable;

import java.lang.reflect.Constructor;
import java.lang.reflect.Method;

/**
 * {@link ParameterNameDiscoverer} implementation which uses Kotlin's reflection facilities
 * for introspecting parameter names.
 *
 * <p>Compared to {@link StandardReflectionParameterNameDiscoverer}, it allows in addition to
 * determine interface parameter names without requiring Java 8 -parameters compiler flag.
 *
 * @author Sebastien Deleuze
 * @since 5.0
 * @see StandardReflectionParameterNameDiscoverer
 * @see DefaultParameterNameDiscoverer
 */
public class KotlinReflectionParameterNameDiscoverer implements ParameterNameDiscoverer {

	@Override
	@Nullable
	public String[] getParameterNames(Method method) {
		if (!KotlinDetector.isKotlinType(method.getDeclaringClass())) {
			return null;
		}

//		try {
//			KFunction<?> function = ReflectJvmMapping.getKotlinFunction(method);
//			return (function != null ? getParameterNames(function.getParameters()) : null);
//		}
//		catch (UnsupportedOperationException ex) {
//			return null;
//		}
		return null;
	}

	@Override
	@Nullable
	public String[] getParameterNames(Constructor<?> ctor) {
		if (ctor.getDeclaringClass().isEnum() || !KotlinDetector.isKotlinType(ctor.getDeclaringClass())) {
			return null;
		}

//		try {
//			KFunction<?> function = ReflectJvmMapping.getKotlinFunction(ctor);
//			return (function != null ? getParameterNames(function.getParameters()) : null);
//		}
//		catch (UnsupportedOperationException ex) {
//			return null;
//		}
		return null;
	}

//	@Nullable
//	private String[] getParameterNames(List<KParameter> parameters) {
//		String[] parameterNames = parameters.stream()
//				// Extension receivers of extension methods must be included as they appear as normal method parameters in Java
//				.filter(p -> KParameter.Kind.VALUE.equals(p.getKind()) || KParameter.Kind.EXTENSION_RECEIVER.equals(p.getKind()))
//				// extension receivers are not explicitly named, but require a name for Java interoperability
//				// $receiver is not a valid Kotlin identifier, but valid in Java, so it can be used here
//				.map(p -> KParameter.Kind.EXTENSION_RECEIVER.equals(p.getKind()) ? "$receiver" : p.getName())
//				.toArray(String[]::new);
//		for (String parameterName : parameterNames) {
//			if (parameterName == null) {
//				return null;
//			}
//		}
//		return parameterNames;
//	}

}
